Infinity Reference 850w, Reference 1050w, Reference 1052w, Reference 1250w, Reference 1252w User Instructions
850w,1050w,1052w,
1250w,1252w
~Innnit){
'j
THANK
YOU
for
choosinganInfinity Reference
Series subwoofer. Reference Series subwoofers
are designed to suit a broad range of mobileaudio applications and
canbeusedina wide
variety
of
enclosure types to produce extended,
powerful bass in a limited amount of vehicle
space.
To
ensure maximum subwoofer performance, we strongly recommend that installation
be
lefttoa qualified professional. Although these
instructions explain
how
to install a Reference
Series subwoofer
in
a general sense, they do not
show
box-construction details or exact installation
methods for your particular vehicle. Ifyou do not
feel you have the necessary experience, do not
attempt the installation yourself, but instead
ask
your authorized Infinity dealer about professional
installation options.
Remember
to
keep your sales receipt with this
manual in a safe place
so
both
are
available for
future reference.
WARNING:
Playing loud music inanautomobile
can
permanently damage your hearing,aswell
as
hinder
your
ability to hear traffic.The maximum
volume levels achievable with Infinity speakers,
combined
with
high power amplification, may
exceed safe levels for extended listening.
We
recommend using low volume levels when
driving. Infinity accepts no liability for hearing
loss, bodily injury
or
property damageasa result
of
useormisuse of this product.
YOUR
CAR
AND
BASS
REPRODUCTION
Dependingonthe
sizeofthe vehicle's interior lis-
tening space, reproduced
bass
frequencies below
80Hz
are boosted by nearly 12dB per octave
as
frequency decreases in the
car.
NOTE:
This effect,
known
as
the vehicle's transfer function, plays
an
important part in shaping the overall in-car
response and
is
displayed graphically along with
freespace response on the enclosed data sheet
for your Reference subwoofer.
CHOOSINGANENCLOSURE
Reference Series subwoofers
are
optimized
to perform best in small sealed, vented and
prefabricated bandpass enclosures. While
infinite-baffle mounting of Reference Series
subs is possible, power handling will
be
greatly
compromised because there's no enclosed
volume
of
air to prevent the speaker's cone
from moving past its limit.
For
this reason, we
do not recommend infinite-baffle mounting for
Reference Series subwoofers.
You
should choose the enclosure you will use
based on the type of music you listen to,
how
much amplifier power you will use for the
subwoofer and
how
much space inside the
vehicle you
can
devote to a subwoofer enclosure.
Because asealed enclosure provides the most
control over the woofer's movement, a woofer
mounted in a sealed enclosure will handle more
power than a woofer mounted
in
another
enclosure type. Sealed enclosures provide more
accurate sonic reproduction than other enclosure
types,
so
they are well suited to all types of
music. Sealed-enclosure construction is straightforward and there are many prefabricated sealed
enclosures available. Optimum sealed enclosures
are
always smaller than other types of enclosures
optimized for a particular speaker,
so
they require
the smallest amount of space inside the vehicle.
Vented enclosures provide better efficiency in
the
40Hz-50Hz
range but this efficiency comes
at
the expense of sound in the lowest octave
(below
40Hz)
andatthe expense of some control
and power handling. If you
are
using asmall
amplifier, a vented box will provide more
bass
output from less power. Vented enclosures
are
also well suited to a varietyofmusic types.
Because vented enclosures require the volume
of the enclosure and the
size
of the port to have a
specific relationship with the characteristics of the
woofer, the enclosure must
be
built exactly to the
specifications provided. While there
are
some
prefabricated vented boxes available, matching
a prefabricated box to a particular woofer is
difficult. If you wish to use a vented enclosure,
we strongly recommend having your authorized
Infinity dealer build it or verify that your design
is
correct ifyou wish to build it yourself. An
optimum vented enclosure
is
always larger than
the optimum sealed box for the same woofer and
will require more space inside the vehicle.
Bandpass enclosures often provide the most
output available from any amplifier and
subwoofer combination at the expense of sonic
accuracy. If sheer
SPL
(sound-pressure level)
is
what you desire most, choose a bandpass
enclosure. Bandpass-enclosure design is very
tricky and the aid
of
a computer and enclosure
design software is necessary. If you
are
an
experienced installerorhave some woodworking
experience, you may wish to build the enclosure
described in the enclosure design sheet included
with this woofer. Fortunately, there are many
prefabricated bandpass boxes available and
they
are
all optimized to extract the most output
possible from any woofer. Bandpass enclosures
can
be
quite large and may require a lotofspace
inside your vehicle.
POWER
HANDLING
LIMITATIONS
The power handling capabilityofany woofer is
related
to
both its ability to dissipate heat and the
maximum
excursion limits of its cone. Once the
speaker's voice coil moves outside the magnetic
gap,
power
can no longerbeconverted into
motion and all the amplifier's power is converted
into heat in the voice coil.This voice coil heating
is
the largest detriment to speaker longevity, so
overexcursion should
be
avoided. Since speaker-
cone excursion
is
different for
each
type
of
enclosure, power handlingisdifferent for
each
enclosure.
Sealed enclosures exert the most control over
the motion
of
a subwoofer because the air inside
the box acts like a spring against the motion
of
the
woofer
cone. Larger boxes allow for more
excursion, thus providing more low-frequency
output
for
the amountofpower used. When
placed in a sealed box much larger than the
Vas
of the subwoofer, it will performasif
it were in
an
infinite-baffle installation.
Vented and bandpass enclosures have the lowest
amount
of
excursion for the amountofsound
output.This
is
a resultofport output reinforcing
the sound output from the woofer. The mass
of
the air contained in the port providesanacoustic
load on the woofer's cone
at
the tuning frequency,
and this added mass decreases woofer-cone
excursion. Vented boxes do not provide adequate
woofer control when driven below the tuned
frequency
(Fb),soproper designisimportant. A
vented bandpass box will have the lowest overall
cone excursion, provided a subsonic filter is used.
• Voice coil overheating and burning due to
overexcursion are often caused by overdriving
an
amplifier into "clipping:' A severely clipped
signal,
or
square wave, contains nearly twice
the power ofa clean sine wave at the same level.
Bass
that sounds broken up
and
distorted
at
higher volumesisusually indicativeofan
amplifier that is clipping and being
asked
to
deliver power beyond its ability.
• Infinite-baffle or "free air" mounting applications allow for greater cone excursion than
subwoofers mounted in
an
enclosure.Inorder
to compensate, the power handling of the
subwoofer will likely
be
half
its
rated power
in this application.
• Study the excursion curves
on
the enclosed
Reference Series data sheet and note the
differences for different enclosure applications.
The type and
size
of box used will produce
different excursion demands
on
the enclosed
subwoofer and, consequently, different
levels of power handling.
As
longasthe
recommended enclosure parameters
are
used, the subwoofer will perform properly
in its enclosed environment. However,
any
design deviation may resultinless than
optimum performance, and may also subject
the subwoofer to overexcursion (i.e., where the
voice coil leaves the gap) that
can
eventually
damage the speaker.
For
additional help with
this issue, please contact your authorized
Infinity dealer.
t\<)
Intfnit'{.
Loading...